President Obama 's decision to target militants from ISIS -- which is now calling itself the `` Islamic State '' or `` IS '' -- operating in Iraq comes as a huge relief to the Iranians . Officials in Tehran have been panic stricken since ISIS forces overran the northern Iraqi city of Mosul on June 10 .

All political factions in Tehran would like to see ISIS suffer and its latest advances rolled back . At the same time , contradictory statements made in Tehran make it clear that the Iranian authorities are divided about the implications of the American military 's return to Iraq .

The moderates , the group of people associated with President Hassan Rouhani 's presidential administration , are nudging toward an open admission that American military operations in Iraq compliment Tehran 's policy goals .

The hawks in Tehran , however , remain reluctant to publicly admit to any shared interests with Washington . Still , overall , Iran and the US are clearly going in the same direction in Iraq , at least while the fight against ISIS rages on .

At first , there was nothing but silence in Tehran as U.S. F-18s on Friday began to target ISIS militants . The silence was more than revealing . In the corridors of power in Tehran , where no opportunity is missed to condemn American foreign policy at every turn , the silence was tantamount to a roaring approval of Washington 's intervention .

On Monday , the moderate faction of President Rouhani took a step to formally spell out its backing for American airstrikes . Not only was Tehran approving but is evidently looking to expand the campaign against `` IS '' and began touting a joint Iranian-American effort in doing so .

Mohammad Sadr , a deputy to Iran 's Foreign Minister Javad Zarif , told an Iranian newspaper `` Iranian-American cooperation against -LSB- IS -RSB- is possible and achievable . '' This was the first time since the U.S . airstrikes began that a senior Iranian official has spoken in such terms .

It is easy to dismiss Sadr as bureaucrat whose words carry little weight in Tehran . But his statement was clearly carefully formulated and was hardly a fluke . And given his stature inside the Iranian system his words must be seen as a peek into the internal policy debate in Tehran about the situation in Iraq and Iran 's options . Some kind of -- at least tacit -- cooperation with Washington is one of those options being studied . Politically , it is already happening .

Tehran and Washington do n't just agree on the need for airstrikes against ISIS . They are also in agreement that Iraq above all needs a new political leadership and that Prime Minister Maliki has to go . Since Monday 's developments in Baghdad and the nomination of a new premier by Iraq 's President Fouad Massmoum , Iran 's reaction has been one of approval of the turn of events .

Maliki 's fate

Today , Ali Shamkhani , the head of Iran 's Supreme National Security Council , gave his unequivocal approval for a new prime minister to take over in Baghdad . No more Iranian dithering on the fate of Maliki it seems .

The fact is that Shamkhani was himself heavily involved in recent weeks to seek out an alternative to Maliki , including a trip he made to Iraq in late July to consult with various Iraqi political circles . The Americans were quicker to recognize Maliki to be at the heart of Iraq 's malaise but the Iranians have finally come around to the same conclusion . And this matters a lot given Tehran 's immense leverage within Iraq 's Shia but also Kurdish political factions .

For Shia Iran , the fight against the extremists from the Islamic State is a critical threat . Tehran desperately wants to keep Iraq intact as a nation state . It is particularly adamantly opposed to Iraqi Kurdistan seceding as Iraqi Kurds have been threatening to do . And in this equation , Maliki had become an unbearable burden for Iranian policy .

The Kurdish leadership that Tehran is so hard trying to cultivate and steer away from an independence bid want Maliki gone .

And Maliki 's woeful management of the Iraqi military 's response to the newly declared `` Islamic State '' made the Iranians just wonder what he was good for . There are reports the Iranian military is engaged in supporting Kurdish Peshmerga forces against ISIS militants . If true , this goes to show the depth of Iranian anxieties about the `` Islamic State 's '' rise in Iraq .

Who 's in driver 's seat ?

As far as the U.S. role in combating the Islamic State is concerned , the Iranian debate is likely to remain split between the moderates and the hawks . The moderates like to focus on the practical challenge at hand in Iraq and ways that Tehran and Washington can collaborate .

They are comfortable with limited tactical cooperation if that is all that can come out of it . And , they readily admit that the neutralization of ISIS needs an American military involvement .

The hawks , immersed in a historic cloak of hostility to the U.S. , can not yet bear to admit to this reality even if they can not fail to see its inevitability . But all the recent trends suggest that the moderate viewpoint in Tehran has the upper hand on the policy question of Iraq and how Iran can best serve its interests .

And President Rouhani seems eager these days to battle it out with his hawkish critics . On the question of the need for Iran to negotiate and cooperate with the U.S. on its nuclear program , he told his detractors this week to go `` to hell . ''

Time will show if Rouhani and his moderate wing can continue to sit in the driver 's seat on the question of Iraq .

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Alex Vatanka writes that Tehran is relieved by the U.S. decision to strike ISIS

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Political hawks in Iran are avoiding admitting shared goals with the U.S. , he says

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But Vatanka says both agree on the need for airstrikes and new leadership in Iraq

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Recent trends suggest that Tehran 's moderates have the upper hand , he suggests